Sealing strip



J. E. GOODMAN SEALING STRIP May 13, 1958 Filed March 21, 1957 INVENTOR.J: .GOODMAN Arrowevs.

United States Patent SEALING STRIP James E. Goodman, Toronto, Ontario,Canada Application March 21, 1957, Serial No. 647,704 Claims. (Cl.72106) This invention relates to a sealing strip, of the type commonlyknown as a waterstop, and the invention is specifically concerned with asealing strip which, when viewed in transverse cross section, isbifurcated in a direction extending parallel to the width of the strip(i. e. the bifurcation extends transversely to the thickness of thestrip).

When using a sealing strip of the type referred to above, the strip issecured to a board forming a bulkhead of a mold in which a concrete slabor form is to be cast, by spreading the arms of the strip formed by thebifurcation and securing them to the bulkhead by means of nails. Thenails are driven in to the bulkhead to an extent sufficient to locatethe sealing strip in position, and the heads of the nails are leftextending clear of the strip so that they can be surrounded by fluidconcrete.

When concrete in a fluid state is poured into the mold, the sealingstrip and the heads of the nails become embedded in the concrete as itsets. The bulkhead is then detached from the nails, and the arms of thesealing strip are manually removed from the nails and moved towards eachother for the arms to lie adjacent each other. The nails are thus leftextending from the surface of the slab or form, and can be used forlocating a caulking strip or the extending ends can be removed.

Further mold boards are then set up at the end of the previously castslab or form, and a further slab or form is cast in edge-to-edgerelationship with the previous one.

The sealing strip is provided with longitudinally extending flutes orheadings which become anchored in the cement as it solidifies sothat-the waterstop will not pull out of its cavity in the event of theadjacent slabs shrinking during the initial hardening of the cement, ordue to a drop in temperature. If, however, the arms of the strip are notsecured together prior to casting of the said further slab or form,there is a very great tendency for air pockets to form between them,which pockets do not become filled with fluid cement. The pockets form aserious hazard to the formation of a satisfactory watertight joint, for,as the temperature of the slabs or forms decreases, the arms, despitethe flutes or beading break away from the surrounding concrete adjacentthe pockets and form paths which permit the ingress of water.

To overcome this disadvantage, it has been necessary, after the bulkheadhas been removed and the arms have moved towards each other, to staplethe arms together in order to prevent the formation of theaforementioned pockets. This is a time consuming operation as thestaples have to be applied at frequent intervals and long lengths ofsealing strip may have to be treated,

An object of the invention is to provide a sealing strip of the kindabove described, in which the need for stapling the arms is obviated.

A further object of the invention is to provide a sealing strip of thekind above described, which can easily and conveniently be manufacturedby extrusion molding Further objects and advantages of the inventionwill be apparent from a study of the following specification Icorresponding dovetail groove 16 formed "arm 14, the dovetail ings, inwhich:

Figure 1 is a perspective view showing the transverse cross section of alength of sealing strip according to the invention;

Figure 2 is a sectional plan view of the sealing strip when positionedin a mold and surrounded by cement;

Figure '3 is a view corresponding to Figure 2, but showing the bulkheadand mold boards removed and the arms of the sealing strip securedtogether; and,

Figure 4 is a view corresponding to Figure 3, showing another concreteform in the process of being cast in end-to-end relationship with theone shown in Figure 3.

Referring firstly to Figure 1, the sealing strip 10 is longitudinallyfluted as is indicated at 11 and is bifurcated for the major portion ofits width, as is indicated at 12, to form two arms 13, 14. As will beseen from the drawings the sealing strip is of slightly greaterthickness at its ends than it is at its central portion.

The sealing strip is preferably formed as an extrusion molding frompolyvinyl chloride, or it may be formed from, for example, natural orsynthetic rubber, or from a suitable synthetic resin.

The arm 13 has a dovetail 15 formed integrally with its surface adjacentthe arm 14 which can be received in a integrally in the 15 when receivedin the groove 16 securing the arms 13 and 14 together. The termintegrally is used herein and in the appended claims to denote that therespective members are formed in one fuse as opposed to being formedseparately and then attached to each other. Y

In use, the arms 13, 14 are separated so that they lie substantially ina straight line with the remainder of the sealing strip extendingsubstantially normal to them, and the strip is secured in that conditionto a bulkhead 18 which is to form the end wall of a mold in conjunc tionwith mold boards 19, 20, as is shown in the Figure 2.

The strip is secured to the bulkhead 18 by means of nails 21 with theheads of the nails extending clear of the arms in such a manner that thestrip is secured sufficiently rigidly to allow the mold to be assembledWithout the sealing strip breaking loose from the bulkhead. When thebulkhead 18 is removed after fluid concrete, indicated by 22, has beenpoured-into the mold and allowed to set, the adhesion between theconcrete and the sealing strip coupled with the taper of the stripprevents the sealing strip from being pulled out of the concrete, thenails 21 during this procedure being pulled out of the bulkhead andremaining extending from the surface of the slab or form. The nails canbe used, if desired, for locating caulking strips (not shown), or theextending ends of the nails can be nipped off or left in situ.

The arm 13 is provided with a flange 13a, which, when the sealing stripis secured to the bulkhead 18, will mask the recess formed by thebulkhead, the dovetail 15, and the arm 13, thus preventing the arm 13from being keyed into the concrete. As will be seen from Figure 3, whenthe arms 13 and 14 are brought together, the lip 13a lies beyond the endof the arm 14.

After the bulkhead 18 has been removed, the arms 13, 14 are movedtowards each other, and pressure is applied to them to force thedovetail 15 into the dovetail groove 16, as is shown in Figure 3. Thiscan be done manually by pressing the dovetail 15 into the groove, or canbe done, for example, by means of a pair of pinch rollers which aretraversed along the length of the strip, the rollers being resilientlybiased towards each other.

The arms 13, 14 are thus easily and quickly secured together by theinterengagement of the dovetail and groove in such a manner that thereis little chance of air pockets of any consequence forming or beingformed be- 3 tween the two arms, thus avoiding the disadvantages abovementioned.

Further mold boards 23, 24 are then set up in end-toend-relationsh ipwith the previously formed slab,- as is shown in Figure 4, and a furtherslab 25 is cast by pouring fluid concrete into the mold so that itsurrounds the extending portions of the arms 13, 14.

What I claim as my invention is:

1. Means for use as a waterstop between adjacent surfaces of concreteslabs or forms, including a strip of a material which is flexible andelastic, the strip, when viewed in transverse cross section, beingbifurcated throughout its length in the direction of the width of thestrip and transverse to the thickness thereof to an extent enabling thearms formed by the bifurcation to be flexed through at least 180relative to each other for them to lie substantially in a common plane,and complementary male and female formations integral with the arms andpositioned for the formations to interlock when the arms are broughttogether for the arms to be in substantially parallel relationship.

2. Means for use asa waterstop between adjacent surfaces of concreteslabs or forms, including a strip of a material which is flexible andelastic, the strip, when viewed in transverse cross section, beingbifurcated throughout its length in the direction of the width of thestrip and transverse to the thickness thereof to an extent enabling thearms formed by the bifurcation to be flexed through at least 180relative to each other for them to lie substantially in a common plane,and complementary male and female formations integral with the arms andarranged in at least one line parallel to and spaced from the junctionof the arms, the said formations being posi tioned for them to interlockwhen the arms are brought together for the arms to lie in substantiallyparallel relationship.

3. Means for use as a waterstop between adjacent surfaces of concreteslabs or forms, including a strip of a material which is flexible andelastic, the strip, when viewed in transverse cross section, beingbifurcated throughout its length in the direction of the width of thestrip and transverse to the thickness thereof to an extent enabling thearms formed by the bifurcation to be flexed through at least 180relative to each other for them to lie substantially in a common plane,at least one female formation integral with one of the arms andextending the full length of the strip, and at least one male formationintegral with the other arm and extending the full length of the strip,the male formation being positioned for it to be entered into the femaleformation when the arms are brought together for the arms to be insubstantially parallel relationship, the male and female formationsproviding interlocking elements of a separable fastener.

4. Means for use as a waterstop between adjacent surfaces of concreteslabs or forms, including a strip formed from a material which isflexible and elastic, the strip, when viewed in transverse crosssection, being bifurcated throughout its length in the directioii of thewidth of the strip and transverse to the thickness thereof to an extentenabling the arms formed by the bifurcation to be flexed through atleast 180 relative to each other for them to lie substantially in acommon plane, and a dovetail extending longitudinally of the strip andintegral with one of the arms which can be received in a complementarydovetail groove in an adjacent surface of the other of the arms, thedovetail, when enteredin'to the dovetail groove, securing the armstogether at a point remote from their common junction.

5. Means for use as a waterstop between adjacent surfaces of concreteslabs or forms, including a strip formed from a material which isflexible and elastic, the strip, when viewed in transverse crosssection, being bifurcated throughout its length in the direction of thewidth of the strip and transverse to the thickness thereof to an extentenabling the arms formed by the bifurcation to be flexed through atleast relative to each other for them to lie substantially in a commonplane, at least one rib formed integrally with one of the arms andextending the full length of the strip, and at least one flange formedintegrally with the other arm of the strip and extending the full lengthof the strip, the rib of the one arm being positioned for it tointerlock with the flange of the other arm to interconnect the arms whenthe arms are moved towards each other to lie in sub stantially parallelrelationship.

References Cited in the file of this patent UNITED STATES PATENTS2,144,815 Robertson Jan. 24, 19159" 2,431,104 Bright Nov. 18', 1 947FOREIGN PATENTS 646,268 Great Britain 1950 1,074,307 France Mar. 31,1954

715,045 Great Britain Sept. 8, 1954

